Standardized traction voltages are 750 V DC, 1500 V DC and 3000 V DC.
The three-phase voltage from the local utility is stepped down and rectified in the traction substations to provide the required DC voltage.
Hitachi ABB Power Grids portfolio covers the complete scope starting from the optimized grid connection down to the conductor rail or overhead line:
- Electrical, mechanical and civil design of the substations
- Medium-voltage switchgear
- Rectifier transformers
- DC switchgear
- Automatic grounding system and low-voltage limiting devices
- Substation automation systems (protection, local and remote control)
- Auxiliary power supply
- Service and maintenance contracts
Special emphasis is placed on optimizing the footprint of the substations. Hitachi ABB Power Grids addresses this requirement with pre-fabricated steel frame (container) buildings or off-the-shelf concrete buildings, allowing for a compact design and a high degree of integration. These pre-fabricated and transportable substations contain all main equipment, station auxiliaries and the station control system.